Charging surface activated by proximity of an object

Abstract

A charging system, comprising a charging surface comprising one or more charging areas associated with a wireless charging device, a plurality of power transmitting coils apportioned among the one or more charging areas, and a controller. The controller may be configured to conduct a low-power search of the charging surface to determine if an electrical or magnetic characteristic of two or more power transmitting coils has been affected by an object passing in proximity to the two or more power transmitting coils, determine a geometric relationship between physical locations of the two or more power transmitting coils, and illuminate one or more indicator lines to identify a physical location of a charging area available to wirelessly charge a chargeable device. The physical location may be selected based on the geometric relationship between physical locations of the two or more power transmitting coils.

What is claimed is: 
     
         1 . A method for detecting an object, comprising:
 conducting a low-power search of a surface to determine if an electrical or magnetic characteristic of two or more power transmitting coils has been affected by an object passing in proximity to the two or more power transmitting coils;   determining a geometric relationship between physical locations of the two or more power transmitting coils; and   illuminating one or more indicator lines to identify a physical location of a charging area available to wirelessly charge a chargeable device, the charging area being selected based on the geometric relationship between physical locations of the two or more power transmitting coils.   
     
     
         2 . The method of  claim 1 , wherein conducting the low-power search comprises:
 providing a pulsed signal to each of a plurality of power transmitting coils, wherein each pulse in the pulsed signal comprises a plurality of cycles of a clock signal; and   detecting a change in resonance associated with each of the two or more power transmitting coils based on response to the pulsed signal.   
     
     
         3 . The method of  claim 1 , wherein changes in the electrical or magnetic characteristic are detected in three or more power transmitting coils, and wherein the three or more power transmitting coils are located along a substantially straight line. 
     
     
         4 . The method of  claim 1 , wherein changes in the electrical or magnetic characteristic are detected in three or more power transmitting coils, and wherein the three or more power transmitting coils are located along an arc of an ellipse or circle. 
     
     
         5 . The method of  claim 1 , wherein changes in the electrical or magnetic characteristic comprise a change in capacitance in a resonant circuit. 
     
     
         6 . The method of  claim 1 , wherein changes in the electrical or magnetic characteristic associated with the two or more power transmitting coils occur when the chargeable device is moved across and displaced from a surface of a countertop or table. 
     
     
         7 . The method of  claim 6 , wherein one or more charging areas are embedded in the surface of a countertop or table. 
     
     
         8 . The method of  claim 6 , wherein one or more charging areas are located under the surface of a countertop or table. 
     
     
         9 . A charging system, comprising:
 a charging surface comprising one or more charging areas associated with a wireless charging device;   a plurality of power transmitting coils apportioned among the one or more charging areas; and   a controller configured to:
 conduct a low-power search of the charging surface to determine if an electrical or magnetic characteristic of two or more power transmitting coils has been affected by an object passing in proximity to the two or more power transmitting coils; 
 determine a geometric relationship between physical locations of the two or more power transmitting coils; and 
 illuminate one or more indicator lines to identify a physical location of a charging area available to wirelessly charge a chargeable device, the physical location being selected based on the geometric relationship between physical locations of the two or more power transmitting coils. 
   
     
     
         10 . The charging system of  claim 9 , wherein the controller is further configured to:
 provide a pulsed signal to each of a plurality of power transmitting coils when conducting the low-power search, wherein each pulse in the pulsed signal comprises a plurality of cycles of a clock signal; and   detect a change in resonance associated with each of the two or more power transmitting coils based on response to the pulsed signal.   
     
     
         11 . The charging system of  claim 9 , wherein changes in the electrical or magnetic characteristic are detected in three or more power transmitting coils, and wherein the three or more power transmitting coils are located along a substantially straight line. 
     
     
         12 . The charging system of  claim 9 , wherein changes in the electrical or magnetic characteristic are detected in three or more power transmitting coils, and wherein the three or more power transmitting coils are located along an arc of an ellipse or circle. 
     
     
         13 . The charging system of  claim 9 , wherein changes in the electrical or magnetic characteristic comprise a change in capacitance in a resonant circuit. 
     
     
         14 . The charging system of  claim 9 , wherein changes in the electrical or magnetic characteristic associated with the two or more power transmitting coils occur when the chargeable device is moved across and displaced from a surface. 
     
     
         15 . The charging system of  claim 9 , further comprising:
 charging modules, each associated with a corresponding charging area and coupled to, or embedded in a surface of a countertop or table.   
     
     
         16 . A charging system, comprising:
 a charging surface comprising one or more charging areas associated with a wireless charging device;   one or more wireless transmitters;   one or more wireless receivers configured to receive reflections of a signal transmitted by at least one wireless transmitter; and   a controller configured to:
 determine that the reflections are received from an object moving across and displaced from the charging surface; and 
 illuminate one or more indicator lines to identify a physical location of one of the charging areas available to wirelessly charge a chargeable device. 
   
     
     
         17 . The charging system of  claim 16 , wherein the controller is further configured to:
 detect a doppler shift in the reflections with respect to the signal transmitted by the at least one wireless transmitter; and   determine presence or movement of the object based on the doppler shift.   
     
     
         18 . The charging system of  claim 16 , wherein the controller is further configured to:
 triangulate reflections of signals transmitted by multiple wireless transmitters; and   determine presence of the object based on triangulation.   
     
     
         19 . The charging system of  claim 16 , wherein the signal transmitted by the at least one wireless transmitter comprises an infrared signal or acoustic signal. 
     
     
         20 . The charging system of  claim 16 , wherein the signal transmitted by the at least one wireless transmitter comprises a radio frequency signal.